A member of our forum community has posted a question regarding his inablity to delete about two-dozen six month old e-mail messages from the inbox of his BlackBerry 7290 with wireless reconciliation activated. He made several attempts to remove the e-mails but to no avail.
Another member offered the following solution, which did the trick:
Using the deskop manager backup/restore, go into advanced, click on "Messages" on the right, click the "<-" (left) arrow, then once it's done transferring, click the right arrow (transferring back to blackberry), it will ask you if you are sure (you are). Then you will be able to delete the messages.
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